The present invention relates to a packaging for storing, transport and/or freezing of a biological material such as fish semen or milt. More particular, the invention regards a packaging for cryopreservation of spermatozoa, embryos or eggs from aquatic organisms.
Traditionally, semen or milt are cryopreserved in cryogenic straw consisting of a narrow and slender tube as for example disclosed in EP 0 873 726 A1, EP 0,562,947 A1, U.S. Pat. No. 5,868,178, and U.S. Pat. No. 5,190,880. The main drawback with these straws is the fact that only small volumes of biological material can be filled into these straws.
Usually, 0.50-1.2 ml semen are frozen in conventional medium cryogenic straw. Trials have been performed freezing 5 ml in comparison with 1.2 ml, resulting in a dramatic decrease in fertilization success (Lahnsteiner et al, 1997: Aquaculture Research 28, 471-479). The aquaculture industry need an efficient large scale cryopreservation protocol and thus preferably a method and means which enables cryopreservation of larger amounts of semen.
Furthermore, it is a well accepted fact that larger and less narrow straw would not be useful since they cannot provide sufficient uniform freezing of the content (e.g. semen), and thus causes reduced quality of the cryopreserved material.
For animal semen, pouches have been proposed for packaging and later artificial insemination of animals. One example of such a pouch is shown in U.S. Pat. No. 7,150,734 and DK/EP 0605406. However, these pouches are not suited for cryopreservation, as the volume is too large to ensure uniform freezing of the full content.